The mesh isn't moving together/ as fast as the bone
If you use Vertex Group in Armature Modifier, be sure Weight Paint of the object is absolutely red.

Or leave Vertex Group field empty.

Be sure other bones (small one) doesn't have influence to the object. Select Armature + Object, switch to Weight Paint mode and click on other bones to see if object is completely blue.
In your case Delete Armature Modifier called &quot;Armature&quot;.